ILLUSTRATION

It is impossible for me to see the absolute difference between drawing and illustration. In my time of study in college, there was a strong line between the two. I think that I separate them to distinguish the commercial illustration from the fine arts world of drawing, but whats the absolute differnce nowadays?. Some illustrations here are applied specifically and others are proposals for things that remain as ideas. With so much more emphasis on photoraphy as a source of illustration, I can see the confusion.